General question: how do you find the equilibrium constant?

Question

aaronq · Answer

let's say you have a chemical equation 

$$ aA+bB <-> cC+dD$$

where lower case are the stoichiometric coefficients and capitals are the species, then
$$K=\frac{ [C]^c*[D]^d }{ [A]^a*[B]^b }$$

all you need now is those values

anonymous · Answer

do you plug in the values?
the M values?

aaronq · Answer

yes, these brackets "[ ]" mean concentration in molarity

anonymous · Answer

b/c I have a question it says $$Br _{2}+Cl _{2}\rightarrow 2BrCl$$ br2 is .006M Cl2 is .0095M and BrCl is 0.15 and it asks for the K value
I plug those values in and I don't get the right answer

anonymous · Answer

i get 263

aaronq · Answer

are you taking into consideration the stoichiometric coefficient on BrCl?

also are you sure thats the right equation, because those 2 elements don't bond to each other..

anonymous · Answer

ohhh didn't do that
I do it now thanks!!

aaronq · Answer

good stuff. Also, forget about what i said about BrCl not binding, they do.